Backflush filter assembly

Abstract

A filter element includes an inner filter basket including an elongated tubular portion having a first open end and a first closed end. The tubular portion defines a plurality of perforations therethrough. An outer surface of the tubular portion is seamless. A first annular brim extends outwardly from the open end of the tubular portion. The filter element also includes an outer filter basket having a second open end in which the inner filter basket is received. A second annular brim extends outwardly from the second open end of the outer filter basket. The fabric filter bag is disposed between the inner filter basket and the outer filter basket.

We claim: 
     
       1. A filter element, comprising:
 an inner filter basket comprising an elongated tubular portion having a first open end and a first closed end, the tubular portion defining a plurality of perforations therethrough wherein an outer surface of the tubular portion is seamless and a first annular brim extending outwardly from the open end, wherein the tubular portion of the inner filter basket has an unperforated strip extending along a longitudinal axis of the tubular portion; and 
 an outer filter basket comprising a plurality of U-shaped wire loops each having a second open end in which the inner filter basket is received, the outer filter basket having a second annular brim extending between ends of the U-shaped wire loops and outwardly from the ends of the U-shaped wire loops, the first closed end of the inner filter basket disposed adjacent the second closed end of the outer filter basket, the filter element having a fabric filter bag is-disposed between the inner filter basket and the outer filter basket. 
 
     
     
       2. The filter element according to  claim 1 , wherein the tubular portion of the inner filter basket has the unperforated strip extending from the open end to the closed end. 
     
     
       3. The filter element according to  claim 1 , wherein the fabric filter bag has an open end and a closed end and wherein a flange defining an elastomeric annular ring is attached to the open end of the fabric filter bag. 
     
     
       4. The filter element according to  claim 3 , wherein the flange is disposed intermediate the first brim and the second brim. 
     
     
       5. The filter element according to  claim 1 , wherein side walls of the inner filter basket are at least 3 mm thick. 
     
     
       6. The filter element according to  claim 3 , wherein the flange and the annular ring are integrally formed of the same elastomeric material. 
     
     
       7. The filter element according to  claim 3 , wherein the flange and the annular ring are formed of different elastomeric materials using a two shot molding process. 
     
     
       8. The filter element according to  claim 3 , wherein the flange has a cylindrical portion to which the fabric filter bag is attached. 
     
     
       9. The filter element according to  claim 8 , wherein the flange has a frustoconical section between the cylindrical portion and the annular ring. 
     
     
       10. The filter element according to  claim 3 , wherein an outer edge of the flange has a generally circular cross section and wherein a diameter of the outer edge is greater than a thickness of the annular ring. 
     
     
       11. The filter element according to  claim 1 , wherein the inner filter basket comprises a plurality of metal bands outside of the U-shaped wire loops that are confirmed to retain the U-shaped wire loops. 
     
     
       12. The filter element according to  claim 1 , wherein the inner filter basket has a generally cylindrical shape.